John dean



NFEI'ERS. PHOTO-LITHOGRAPHER. WASHINGTON D C .geiten tatrsatrat-I @frn 'ALEXANDER CESAR FREDERICK FRANKLIN, 0F NO. 4 PRINGES SQUARE,

BAYSWATER, ENGLAND.

Letters .Patent No. 81,766, elated Septemder 1, 1868.

IMPROVEMENT IN REGIPROGATING STEAMENGINES.

TO ALL TO WHOM ITMAY CONCERN: l

Be it known that I, ALEXANDER CmsanFnnDEnIcK FRANKLIN, of 4 Princes Square, Bayswater-England a subject ofthe Queen of Great Britain, have invented or discovered new and useful Improvements in Steam- Engines, and I,` the said ALEXANDER Cassin FREDERICK FRANKLIN, do hereby Vdeclare the nature of the said invention, and infwhat manner thc same is to be performed, to be particularly described and ascertained in and by the following statement thereof; that is toisay- This'invention has for itsobject improvements in steamengines, and vis applicable where two cylinders' are employed, the vpistons of which are connected to one crank-shaft. The number ofthe cylinders may, how.-VA ever, be'more than two. l l

The invention'consists in .so arranging the engine that the Asteam only acts on each piston, to move it in one directionso that if two cylinders be employed, the pressure of the steam will he acting'on the piston of one cylinder, and thus turning the crank-shaft, whilst the piston of the other cylinder is being moved back without being acted on by the pressure of the steam. It should .be observed that when the cylinders open' in opposite directions, the two cranks should project from their shaft in one direction, but when the two cylinders open in the same direction, the two cranks should project in opposite directions from( their shaft.' And in order that my said invention may be most fully understood, and readily carried into effect, I will proceed to describe. the drawings hereunto annexed. u

.Description of the Drawings. Figure 1`is a plan of a steam-engine, arranged according to my invention, and having two stationary steam-cylinders. a a is a base-plate, on which are bolted Vthe two' steam-cylinders 6 b, each of which is open fat one end to the air. One of the cylinders is open in front the stung-box, for ,the piston-rod being carried by means of a bar passing from side to` side of a ring-cover, such as is shown in planl in Figure 2. ',lfhe'other steam-cylinder, which is open 'at the'back, may be fitted with a ring-cover, such as is shown at Figure 3. The steam-passages are to be arrange-d inthe usual way, except that the passage leading to the open end of each cylinder should be stopped up or dispensed with. b. b are valve-boxes on the sides of thecylinders. .Theymay contain slidefvalves, of ordinary construction, and they are to be supplied with steam in the usual way. The piston-rods c c arejointed at their'outer ends tothe conncctingwods old,iwhicl 1 at their other extremities are coupled with cranks e e', on the driving-shaft e, as is shown. ff are eccentries on the shaft e, for giving motionto the valves in utheusual way. g is a {1y-wheel, and h a belt-pulley; to receive an endless strap, for driving machinery. Both of themare fixed upon the driving-'shaft e. k

It' preferred, the valves of thel steam-chests maybe so arranged and provided with actuating-mechanism that the steam shall be exhausted fromthc cylinder 'at about half stroke, and I sometimes place valves in the lexhaast-passages, such valves being arranged so that when the pressure in the cylinder falls to the atmos: pheric pressure, the valvein the exhaust-passage closes, Vand froml the continued motion of the pistona` partial vacuum results, which is utilized in the return-stroke.

I would remark that the form of the engines may be varied. Thus, the p'istons may'ha-ve trunks upon them to admit'oil the connecting-rods being coupled' at once with the piston, or the cylinders may be arranged to oscillate' onv trunnions, as is well understood, and other similar variations may be made.

In' the practical working of the above-described arrangement of open cylinders, with pistons and cranks, the steam, while driving one piston, operates, through the driving-shaft and cranks, to eiiect the return movemerit of the other. If the two cylinders bearranged with their ends open in the same direction, and the cranks arema'de to project in the samefdirection, theengine-will not operate so as` to e'ect a full revolution of the shaft. So, should the cranks be arranged to standin opposite directions, and the cylinders be -made to open in opposite directions, the enginewill not turn the shaft au entire revolution. The arrangement involved by my invention, therefore, contemplates that either the two cranks should be arranged in opposite 'directions with respect to each other, and both the cylinders be open in one direction, or both the latter shall open in opposite directions, and the cranks be arranged to project in the same direction.

I therefore claim my'improvcd engine, constructed substantially as described, that is, with each cylinder open at one end only to the atmosphere, and with the cranks of the driving-shaft and the connecting-rods of the pistons of such engines arranged to project from the shaft in the manner herein described.

A C. F. FRANKLIN.

Witnesses: v i 1 JOHN DEAN, 17 Gacechurch Street, London. T. A.` FRANKLIN, 4 Princes Square, London. 

